SOLUTION: Mean equal to 15 and standard deviation equal to 5. Find the probabilities associated with getting: a. A 15 or above b. Between a 15 and an 18 c. A 13 and above

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Question 90232: Mean equal to 15 and standard deviation equal to 5. Find the probabilities associated with getting:
a. A 15 or above
b. Between a 15 and an 18
c. A 13 and above
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Mean equal to 15 and standard deviation equal to 5. Find the probabilities associated with getting:
a. A 15 or above
Since 15 is the mean,P(15 or above) = 1/2 or 0.50
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b. Between a 15 and an 18
15 has a z-score of 0; 18 has a z-score of (18-15)/5 = 3/5=0.6
Using a z chart P(0 ----------------------
c. A 13 and above
P(z>0.6) = 0.50001-0.2257 = 0.2743
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Cheers,
Stan H.